Our trip to the Izu Islands is scheduled for mid-July through mid-August. This is not the optimum time in terms of weather
conditions (hot and humid!) and there is the chance of typhoons. Nevertheless, the dates are set and we are looking forward
to a sultry time in Japan. The fieldwork will take place in three stages:
- Stage (1)
- The first trip will target 3 volcanoes:
We plan to travel to these islands using regular ferry services that leave from Tokyo and the Izu Peninsula. Oshima is located due east of the Izu
Peninsula and is the largest of the Izu Seven Islands (about 91 square kilometers). It is home to the active volcano Mt.
Mihara-yama which last erupted (big time) in 1986. Nii-jima is located to the SSW of Oshima and is much smaller (~ 23 sq. km).
It is renowned for its big waves, white sands and beautiful beaches. Nii-jima is comprised of 8 lava domes which occur in 2
groups at opposite ends of the island. The Mukai-yama complex at the southern end of the island and Achi-yama lava dome at
the northern end were formed during Nii-jima's only historical eruptions in the 9th century. Shikine is a small island 6 km
south of Nii-jima. It has lots of hot springs.
- Stage (2)
- The second part of the expedition will concentrate on the southern islands in the Izu chain. After returning to the
Mainland after the first trip, we will fly to
Hachijo-jima which is about 300 km south of Toyko. It has 2 volcanoes - Higashi-yama
volcano occupies the SE end of the 14-km-long island, and the symmetrical Nishi-yama volcano the NW end. Nishi-yama has been active in historic
times. Hachijo-jima will be the stepping stone for our visit to
Aoga-shima, 75km to the south, and not technically part of the Izu Seven
Islands. It is a small, 2.5 x 3.5 km, island surrounded by steep cliffs, and reached by helicopter. It was last active in 1785. After Aoga-shima,
we will return to Hachijo-jima and then to Toyko.
- Stage (3)
- The final part of the trip is on-land so we can drive to these 2 localities from Toyko (link). The first is the complex volcano -
Hakone. It comprises two overlapping calderas formed about 180,000 and 49,000-60,000 years ago. There are numerous hot springs in the region
and these will be our targets for sampling. The last volcanic activity at Hakone was about 2,900 years ago. The final volcano on our itinerary
is perhaps the most famous.
Mount Fuji is Japan's highest and most noted volcano. Its near perfect conical shape has been constructed by
voluminous lavas flows starting at about 11,000 years before present. The last major eruption was in 1707 and ash was deposited on Tokyo about
100 km away. The "climbing season" for Fuji-san (as it's reverently referred to) is July-August so we hope we have enough time at the end of our
trip to do the hike to the summit.
So to summarize the logistics of our trip: in our quest for samples from the northern segment of the IBM system, we are planning to use
ferries, planes, cars, helicopters and feet to collect the precious volcanic gases of the Izu Islands and Mainland volcanoes.